Electric combination switch



06L 1953 CLAUS-HOLMER GERDES 3,105,888

ELECTRIC COMBINATION swncu 2 Sheets-Sheet 1 Filed May 26, 1960 /NVNTOP (laug- Halw-r (1mm .mm, mm a 1963 CLAUS-HOLMER GERDES 3,105,888

ELECTRIC COMBINATION SWITCH Filed May 26. 1960 2 Sheets-Sheet 2 mestem, (Ross 8* mstem 3,105,888 ELECTRICCOMBINATION SWITCH Claus-Helmet Gerdes, 18a-b Carl Peters Strasse,

,7 Luneburg, Germany 7 Filed May 26, 1960, Ser. No. 31,96 Claims priority, application Germany May 28, 1959 3 Claims (Cl.'20081.5),

This invention relates to an electric combination switch capable ofpenforming a number of functions.

Electric switching devices with several'o perative functions are .well known in the art. It is likewise known to provide a plurality of switching elements separate from one another in the apparatuses which are to be controlled by such switching devices, but these constructions are open to serious objections which" are particularly noticeable, in assembling, wiring and operation and which add to the cost of production.

The object of the invention is to avoid these objections and to achieve'aconsiderable technical advance in the art by combining operative functions, such as pressure and temperature differences of a liquid, in an adjustable common switching operation in astandard device.

This is attained according to the invention by the provision of an electric combination switch actuated by presumed ta e Pat t-JO sure and temperature impulses, wherein by the simultaneous use of new features and of known features used in a diiferent manner, such as individuallyregulatable and adjustable switching impulse and signal contact transmitters which are preferably dependent upon pressure and temperatom or upon diiflferences in pressure and temperature and act on ai common bridge-shaped switch element which simultaneously actuates different switching and signalling contacts.

A p-referredembodiment of the invention will now be described by way oiexample and with reference to the accompanying drawings, in which n FIG. 1 is a top plan view of the base plate of a'combination switch according to the invention;

FIG. 2 is a bottom plan view of the base plate;

FIG. 3 is a top plan view of the switch bridge of the switch;

FIG. 4 is a top plan view of the contact bridge;

FIG. 5 is a diagrammatic simplified view of the combination switch in side elevation, and

FIG. 6 is a sectional view showing the rod with rod guide and packing cap.

As shown in FIGS. 1 and 2 an electric combination switch according to the invention consists of a base plate 1 which has a fiat underside 2 and can be connected, if necessary with an interposed packing 3 (FIG. 5), with an apparatus, not shown, whose functions are to be controlled. The base plate 1 has, in addition to fixation holes 4, a bore 5 for the passage of a push rod 6 (FIGS. 5 and 6) which is operated, for example, by a differential pressure diaphragm, not shown. Furthermore, the base plate 1 has a recess 7 which accommodates a thermobimetal strip 8 (FIG. 5) adapted to act in the path of flow of a heated liquid. The thermo-bimet'al strip 8 is fixed at one of its ends by a screw 9 in the recess 7 of the base plate 1. Above the other end of the strip 8 the base plate 1 has a bore 5a by which a push rod 6a is guided with tight fit. 1

The base plate 1 has also two bores 10 for receiving two spacer bolts 11 which carry a contact bridge 12 as shown in FIG. 5. This contact bridge 12 is provided with terminal screws 13 (FIG. 4) for fixing electric wires 14 f circuits which are to be closed and opened by the switch. With the object of simplification, the spacer bolt screws built-in push 15 engaging the contact bridge 12 can also be used for 3,105,888 Patented Oct. 1, 1963 2 are connected to a common switch bridge 18 by means of leaf springs 17. These leaf springs 17 are adjustable by means of set screws 19 in order to insure simultaneous making and breaking of the circuits by resiliently hearing against counter-contacts 20 on the base plate 1.

The current feeding parts of the switch bridge 18, such as the contacts 16 and the set screws 19 of the leaf springs 17 are protected in relation to each other against flashover in humid atmosphere by ribs 21 formed on the switch bridge 18 Similarly the counter-contacts 20 with terminal screws 13a of electric wires 14b are protected against flashover by ribs 21a formed on the base plate 1.

The switch bridge 18 is pivotally mounted on a hinge 22 provided at the end of the base plate 1 remote from the set screws 13a. Behind the contacts 16 the ends of two tension springs 17 are attached to the switch bridge 18, whereas the other ends of these springs are connected to astrap 23. i f

A metal tongue 24 isrigidly connected with this strap 23wand connects said strap with the base plate l. One end of a leaf spring 25 is rigidly connected to the con-tact bridge 12 while the other end of this spring 25 presses against the metal tongue 24. The pressure exerted by this leaf spring 25 can be adjusted by means of a set screw 27 extending through a threaded hole 26in the contact bridge 12. Thus the resilienrcounter pressure of the switch bridge 18 pivotatble about the hinge 22can be adjusted. The push rod 6 guided in the bore 5 in the base plate 1 bears against the underside of the meta-ltongue 24 and is actuated by the transmitter of the pressure function,'ior example of a diaphragm not shown in the draw- I In line with the contacts 16 a counter part 28 to the push rod 6 actuated bythe thermo-bimetal strip 8 is adjustably mounted'on the switch bridge ISby means of a screw thread so that the transmission of the control movement of this function can be accurately set. This arrangement as a whole constitutes a switch combination capable of being actuated by several control functions the individual control impulses of which can be set to predetermined values with the result that the intended operating procedure, namely the making and breaking of given current circuits is ensured.

The contact of a pilot or signal lamp can at the same time be actuated by the contacts under operating current. The arrangement for the contact-making of this signal lamp can be such that the circuit for the lamp is closed when the operating current circuit is interrupted, for example by the transmitting elements of the function transmitter coming into contact.

The sealing of the push rods of the pressure differential diaphragm not shown and of the thermo-bimetal strip 8 is effected in the same manner so that it will suflice to describe the construction of the push rod 6 of the pressure diilerential diaphragm, which construction is shown in FIG. 6. The push rod 6 has in its lower portion a plateshaped collar 30 with a rounded edge 31. This collar 30 is surrounded by a packing cap 32 having an upper open end provided with a bead 33 which is pressed aaginst the base plate 1 by a screwed-in push rod guide 34. Be-

low the collar 30 the push rod 6 has a screw-threaded end 35 which passes through the lower end of the packing cap 32 and carries a nut 36 which tightly presses the flexible packing cap 32 against the push rod 6.

The free end of the push .rod 6 is rounded so as to ensure uniform contact with the metal tongue 24 of the differential pressure actuating means.

As compared with the known state of the art, this construction of the push rods and of their packing cap results in a particularly short transmission element for the impulse transmitter while retaining very small diameter.

The invention may be embodied in other specific forms Without departing from the spirit or essential characteris tics thereof. The present embodiment is therefore to be considered in all respects as illustrative and not restrictive, the scope of the invention being indicated by the appended claims rather than by the foregoing description and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

I claim:

1. An electrical switch responsive to changes of at least two physical parameters, comprising a base provided with a first contact, a contact bridge sWingably mounted on said base for angular motion in a plane generally transverse thereto, said contact bridge being provided with a second contact engageable with said first contact in one angular position of said bridge, a spring-supported member aflixed to said base and extending above said bridge, a leaf spring depending from said member and bearing upon said bridge for urging said bridge into said position, and control means for urging said bridge out of said position against the eifect of said spring means, said control means including at least two pins transverse-1y shifta'ble in said base and engageable with said bridge, each of said pins being displaceable in response to a variation in one of said pa rameters.

2. An electrical switch responsive to changes of at least two physical parameters, comprising a base provided with a first contact, a contact bridge swingably mounted on said base for angular motion in a plane generally transverse thereto, said contact bridge being provided with a second contact engageable with said first contact in one angular position of said bridge, spring means for urging said bridge into said position, said spring means including at least one tension spring secured at one end thereofto said bridge, a tongue pivotally secured to said base and engaging the other end of said tension spring, thereby tending to swing said bridge out of said position, aspringsupport member afiixed to said base and extending above said bridge, a leaf spring depending from said member and bearing upon said tongue, thereby biasing said bridge normally into said position, and control means for urging said bridge out of said position against the net effect of said i springs, said control means including at least two pins transversely shiftable in-said base in response to a variation in one of said parameters, one of said pins being engageable with said tongue,.the other of said pins being engageable with said bridge.

3. An electrical switch responsive to changes of at least two physical parameters, comprising a base provided with a first contact, a contact bridge swingably mounted on said base for angular motion in a plane generally transverse thereto, said contact bridge being provided with second contact engageable with said first contact in one angular position of said bridge, spring means for urging said bridge into said position, said spring means including at least one tension spring secured at one end thereof to said bridge, a tongue pivotally secured to said base and engaging the other end of said tension spring, thereby tending to swing said bridge out of said position, a springsupport member afiixed to said base and extending above said bridge, a leaf spring depending from said member and bearing upon said tongue, thereby biasing said bridge normally into said position, a manually operable adjusting screw carried by said support member and engageable with said leaf spring for adjusting the force with which it biases said bridge into said position, and control means for urging said bridge out of said position against the net effect of said springs, said control means including at least two pins transversely shiftable in said base in response to a variation in one of said parameters, one of said pins being engageable with said tongue, the other of said pins being engageable with said bridge.

References Cited in the file of this patent UNITED STATES PATENTS 

1. AN ELECTRICAL SWITCH RESPONSIVE TO CHANGES OF AT LEAST TWO PHYSICAL PARAMETERS, COMPRISING A BASE PROVIDED WITH A FIRST CONTACT, A CONTACT BRIDGE SWINGABLY MOUNTED ON SAID BASE FOR ANGULAR MOTION IN A PLANE GENERALLY TRANSVERSE THERETO, SAID CONTACT BRIDGE BEING PROVIDED WITH A SECOND CONTACT ENGAGEABLE WITH SAID FIRST CONTACT IN ONE ANGULAR POSITION OF SAID BRIDGE, A SPRING-SUPPORTED MEMBER AFFIXED TO SAID BASE AND EXTENDING ABOVE SAID BRIDGE, A LEAF SPRING DEPENDING FROM SAID MEMBER AND BEARING UPON SAID BRIDGE FOR URGING SAID BRIDGE INTO SAID POSITION AND CONTROL MEANS FOR URGING SAID BRIDGE OUT OF SAID POSITION AGAINST THE EFFECT OF SAID SPRING MEANS, SAID CONTROL MEANS INCLUDING AT LEAST TWO PINS TRANSVERSE SHIFTABLE IN SAID BASE AND 